﻿using System;
class Rectangle
{
    private double length;
    private double width;
    public Rectangle(double length, double width)
    {
        this.length = length;
        this.width = width;
    }

    public double CalculatePerimeter()
    {
        return 2 * (length + width);
    }

    public double CalculateArea()
    {
        return length * width;
    }
}

class Program
{
    static void Main(string[] args)
    {
        Rectangle rect = new Rectangle(5, 3);
        Console.WriteLine("长方形的周长为：" + rect.CalculatePerimeter());
        Console.WriteLine("长方形的面积为：" + rect.CalculateArea());
    }
}